This has been bugging me for a bit. I have an irrational attraction to GMT complications, as much as an irrational dislike for chronographs. And prefer sub-40mm size.
Had a 856 UTC and I convinced myself it was marginally too large for my wrist, so I sold it to finance purchase of a 556A. Which I absolutely love for daily wear.
And after kicking around WUS and Sinn/Watchbuys websites, I found out about the Frankfurt Financial district models, with 12hr bezels, fell in love, and recently picked up a 6068NK.
But I also found out about the Diapal tech, specifically the 756 model with "UTC" hand. In quotes because far as I can tell, it it slaved to the hour hand as a 12hr dual-time zone indicator, rather than a true 24hr function like with the 856 UTC running the ETA 2893-2 movement.
(photo stolen from michael-m, Show your Sinn thread)
So the questions in my head are:
Why does the 12hr "UTC" hand seem to be proprietary to Diapal tech models? Is there something about Diapal conducive to the second hour hand that regular movements can't support? Does it have more to do with the chrono movement functions? How is it adjusted -- at the 2/date position on the main crown?
Would love to see it in a 556-size case, but would also settle for the additional hour hand in an 856, or even 856 UTC for 3 time-zone function.